Dental chair.



PATENTE MAY 14, 1907.

o..53,421l A RRITTER." DENTAL GHAIR. APPLIUATION PIED SEPT. 18. IDOL Inventor.

PATBNTBD MAY 14, 19071' APPLICATION FILEI SEPT. 418. 1901.

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I Attoz-ney FRANK RITTER, OF ROCHESTER, NEW YORK.

DENTAL CHAIR.

'Specification of Letters Patent.

Patented May 14, 1907.

Application filed September 16,1901. Serial No. 75,569.

To all whom, t may concern:

Be it known that I, FRANK RITTER, of Rochester, in the county of Monroe and State of New York, have invented certain 5 new and useful Improvements in Dental Ohairs;and I do hereby declare the following to be a full, clear, and exact description of the same, reference being had to the ac companying drawings, forming a part of this specification, and to the reference-numerals marked thereon.

My present invention relates to adjustable dental, surgical or barbers chairs andit has for its object to provide an improved form of standard and elevating mechanism which shall be compact and adapted to permit a vertical movement of the chair ofconsiderable latitude from its lowest to its highest position, and to support the seat rigidly at any desired position of adjustment and also to guide the chair in such a manner that it ,-may be operated smoothly.

1t has for its further object to provide a controlling device whereby the movement of the chair is automatically controlled to revent jarring when it approaches the limit of its downward movement.

To these and other ends the invention consists in certain improvements in construction 'and combinations of parts, all as will be hereinafter fully described, the novel features being pointed out in the claims at the end of this specification.

In the drawings: Figure 1, is a vertical sectional view on the line t-t of Fig. 2, showing the elevating mechanism constructed in ac cordance with my invention showing the chair seat in section. Fig. 2, is an enlarged sectional view on the line of Fig. l. Fig. 3, is a similar view on the line y-y of Fig. l. Fig. 4, is an enlarged side elevation of the ram cylinders, showing a portion of the casing in section, and taken on the line e-z of Fig. 2. Fig. 5, is an enlarged sectional view of the ram controlling valve, and Fig. 6, is a cross sectional view on the line s-s of Fig. 5.

Similar reference numerals in the i'gures indicate similar parts.

The mechanism formingthe subject of this invention embodies a collapsible and preferably telescoping standard and alifting mechanisin which ferm a sappert fer the chair, the seat frame 1 of which latter is shown in section, the lower standard section or pedestal 2 being revolubly mounted in av cylindrical several base 3 and supported on an annular flange 4 engaging the top of the base and having near its lower end a bearing surface 5 cooperating with a similar surface upon the interior of thc base to insure stability of the parts. The base 3 is closed at the bottom and adapted to contain oil or other liquid by means of which the hydraulic lifting mechanism is operated, and it is mounted upon a broad rim 6 resting upon the floor and to which it is attached by means of screws 7.

Mounted in the pedestal is a vertically movable cylindrical intermediate standard section 8 having its upper end projecting` through an adjustable collar 10 and having its lower end provided with the outwardly extending lugs 11 embracing the guide rods 12 rigidly supported, by the lugs or ears 13, in the pedestal. Arranged within the section 8 on the lugs 15, are similar guide rods 16 carrying a frame 17 attached to the lower end of the upper telescoping standard section 18 the u per crtion of which projects through an a justa le collar 19 in the top of the section 8 and is attached to the seat frame 1 by any suitable means. ln the present instance I have shown the seatframe provided with a cross bar 20 which is attached to the said sec# tion by dowel pins 21 and a screw 22 which is provided with an aperture 23 through which the oil or other liquid may be conveniently supplied to the interior of the base by remov ing the closure cap or screw 24. The upward movement of the section 18 is limited by a lug 25 on the frame 17 which abuts against the inner side ofthe head on the section 8 and in a recess in the lug is a spring 26 which prevents a sharp contact between the parts.

The operating pump is similar to the one shown in my prior Patent No. 619,226, granted Feb. 7, 1899, and consists generally of the cylinder 30 having the inlet check valve 31 opening from the base 3 into the cylinder, and the outlet check valve 32 communicating with the passage 33 leading to the regulator valve. The regulator consists of avalve stem 34 closing the end of said passage and adapted when raised by the pressure of the liquid to allow it to flow outward through the passages 35 in the valve casing opening within a hood'36 the lower open end of which is adapted to lie below the surface of the liquid in the base 3. The valve stem is normally held in a closed position by a spring 37 lying beneath a screw 38, in a recess formed inthe side of the pedestal, and operating a plunger 39 bearing IOO " in the pedestal and operates at the side and against the inner end ol a releasing lever 4() which lies between. it and the stem 254. 'lhe lever is pivoter] at 4l and by applying pres .sure to the outer end ol the lever the plungt-ir 39 will compress the spring 37 and |wrmittl1e valve to be raised by the pressure el' the liquid. A set screw 42 located ou the lever is adapted to engage the side olf the pedestal to limit its movement. Operating in the pump cylinder .is the piston head 45 to which is attaelll-id the rod 46 ad api ed to be mov ed in one direction by the stud or pin 47 on au oscillatory slutlt 4H, journaled in the pedestal Z and having :'Lttached. to its out-er end. an operai ing lever 4S) (shown in dott-ed lirios in l*1 ig. 2). Attached. to the upper' end o'l' the red 46 is a spring 5() by means of which the piston and. lever 49 are returned to normal posh ion a'f'ier each operation. The pump and the devices operated thereby are supported by means of a hollow spider or frame 5]. bolted or otherwise secured. to the ears or lugs 51, upon the inner side of' the pedestal so that as the latter is revolved within the base said parts are carried therewith.

'.lhe elevating mechanism is mounted withcxterior of the 'telesci'ipic guide section 18 and it consists of a rain embodying a stationary cylinder 52 which communicates, at irs lower end with the passage 33, and is provided with a movable 'telescopic cylinder or section 53 in which operates the ram plunger 54 provided with the piston head 55 having the usual packing'. The movable cylinder constitutes a piston and is also provided with the piston head 56 having he central aperture 56 and i ts upper end projeciingabove the guide'section S is providr-fd with a cap 57 surrounding the ram plunger 54 and containing packing or a wiping washer A dust hood or pro toeter in the form oi' a tube 60 is attached to the cap and surrounds the movable cylinder 53 having its lower end extending in proxim ity to the upper end of the stationary cylinder 52 when extended, where it is provided upon the exterior with a lug 6l having an aperture through which extends a rod 62, connected at its lower end to the spider or frame 5]. and at its upper end provided with a nut or head 63 (see Fig. 4) for limiting the upward movement of the cylinder 53.

64 is a coil spring located between the lug 6]. and the head 63 to quietly arrest the move* ment of the cylinder and prevent it jarring against the stop when reaching the limit of its upward movement.

The upper end of the ram plunger 54 engages the cross bar on the seat frame and in operation the liquid supplied by the pump passing into the cylinder 52 raises the movable cylinder 55j and the ram plunger, carrying with them the seat frame, the liquid passing through the aperture 56 in the head 56.

secured thereon by means of an apertured The eXtreme upward movement of the cylinder is limited bythe stop (5I-l and lug l. 'lbe tube (il) carried bythe movable cylinder protects the latter from dust as well as preventing contact with its oily surl'aoe and tbe ap ertures 65 located inv the cap 57 belovil the pac-,king 58 allows any liquid that may work past the head 55 to be returned into the base 3 througli the passage between the hood or casing andv the cylinder' without showing on the exterior ol the base, or being exposed to catch dust ete.

It has been heretofore exi'ilained that the downward movement of the chair is controlled by the stem 34 in the regulator valve and when it is desired to lower the chair the valve being opened by the releasing lever 4() the liquid is allowed to escape into the base from the passage 33 permitting the ram plunger 54 to descend, its head 55 engaging the spring 68 on the piston head 56 in its con? tinued downward movement. In order to automatically cushion the parts as the chair approaches the limit of its downward movement, I provide a graduating valve device carried by the movable cylinder or piston section 53 which will control the outward flow of the liquid therefrom to gradually diminish the movement of the plunger with the piston section 53 and chair until it is at its normal position of rest. Arranged in the central aperture 56 is a tubular stem 75 movable longitudinally in the piston head 5G and secured therein by means of an annular flange or rim 76 at its upper end engaging a similar rim on the head and normally held in contact therewith by a spring 7 7 the tension of which maybe regulated by a hollow screw 78 also servin to hold. it in place. At the lower end of tie stem is a disk or valve 7 9,

screw S0, and adapted to engage with an annular seat 81 in the bottom of the stationary cylinder 52 and above the apertures 82 which connect said cylinder with the passage Arranged in the side of the stem is an aperture 83 located just below the face, of the piston head 56 to permit the Vpassage of the liquid from between the valve 79 and head 56, at first when the valve engages the seat 81., the subsequent movement of' the cylinder or section 53 being controlled by a longitudinal slot 84 the bottom of which eX- tends at an angle to the side of the stem so that the upper end of the slot has the greater depth and its area constantly decreases as it approaches the valve at the lower end of the stem. When the parts descend in the cylinder 52 the valve 79 engaging the seat 8l prevents the outward movement of the liquid included between the valve and the piston head 56 which at first can escape through the aperture 83 and later` only through the slot 84 the area of which is gradually diminished as the piston 56 descends thereby regulating the low ofthe liquid ywhich passes outwardly IOO IIO

4ard therefor embodyi sure on op osito sides of the disk or valve 79 is balancer1 and the disk and stem are projected but when said disk is arrested the only Vescape for the liquid is through the reduced passage arresting the seat gradually and without jar.

The lii'tinv mechanism describednrespec tive of the checking device on the end of the ram pionier enables me to give to the seat a considera le variation oi adjustment and facilitates repairs and repaclnng ci' the pistons when desired without entirely diementlinu' the chair, at the same time by locating theliiting plunger forward of the standard, provide an. increased bearine on the seat frame to prevent binding of the standard o'aiding sections when the patients Weight 1s on the forward platform of` the chair. This bearing of the plunger on the seat or chair is far enough Jforward to permit these results .to be accomplished and at the saine ltime it permits the use of cylindrical stand# ard sections.

I claim as my invention:

l. The combination With a base, a telescopinfr standard therefor embodyinor the lower, intermediate and upper standar sections revolnbly mounted on the base and a chair mounted on the upper-section, oi a 'telcscoping lifting mechanism embodying a lower stationary cylinder, an intermediate movable cylinder and a movable plunger all located within the intermediate standard section and arranged exteriorly of the upper section and a tubular guardiconnected to the upper end 'ci the intermediate cylinder and extending over the lower cylinder in the-intermediate section when the chair is raised.

2. The combination with a base, a standa plurality of telescoping sections and a c lair connected to the upper one of said sections, of a :hydraulic lifting mechanism, arranged exterior y of the section connected to the chair, embodying the stationary and intermediate and upper movable sections, collapsing Within the other standard sections, a tubular sleeve at! tached to the intermediate li'ftin section and extending over the latter and t e lower lifting sections.

3. The combination with a chair and an extensible standard therefor, of a hydraulic liiting mechanism for the chair embodying a cylinder and a. piston head operating `therein, a 'duid escape passage leading from the cylinder beneath the piston head, and a valve for controlling 'the oW of liquid through the escape passage closed by the descent o' said head, and a contracted fluid escape passage or by-pass connecting the cylinder, between the piston head. and valve, With the luid escape passage.`

Yupper end of the intemnediatc cylinder |lifting 4. The combination With extensible telescopre standard sections and a chair mounted on one ci' them, of a hydraulic lifting mechanl ism arranged exteriorly of the section connected to the chair, embodying a stationary cylinder, an intermediate movable cylinder tting the former and an upper movable piston in the intermediate cylinder engaging the chair, a tubular cover or casing connected to the upper end of the intermediate cylinder and extending over the lower stationary cylinder into its inclosing portion of the standard and i'lrid esca epassages between the cover and its cylin er.

5. The combmationwith telesco I:ving standard sections and a chair mounted on one of them, of a hydraulic lifting mechanism arranged exterior oI' the section on which the chair is moe nted, embodying a lower station ary cylinder, an intermediate movable cylin der and an upper movable piston engaging the chair, a tu ular cover connected to thi an extending into the other sections of the standard and scrroimding the lower stationary cylinder and. a stop cooperating with the cover to limit the upward movement of thc intermediate cylinder.

6. The combination with the chair and an extensible standard therefor, oli a hydraulic mechanism embodying a lower stationary cylindcl; an intermediate movable cylinder and a movable piston operating in t e cylinder and coperatinc with the chair,

. the ca piece connected to the end oi the intermec'ate cylinder havinfr apertures con necting with the interior thereof, the outer tubular cover carried onthe movable cylinder and extending over the lower cylinder 'and a Wiper arranged inthe cap abo-vc the apertures.

7. The combination with a chair, and an, extensible standard, therefor, ci a hydraulic lifting mechanism embodying the lower stationary cylinder, the intermediate movable cylinder and the inner piston operating up on t 1e chair, the tubular cover connected to the upper portion of the intermediate cylinder an extending over the lower cylinder into one ofthe sections of the standard and having the rejection at the bottoni and the rod" with W ch said projection coperaties to limit the n' Ward-movement of the intermedicte cylin er.

8. The combination With a chair and an extcnsiblestandard therefor, of hydravic lifting and lowering mechanism embodying a cylinder, a piston movable therein and operating upon the chair, e. ilnid discharge assage from the cylinder, a valve monate on the vpiston adapted to close the fluid discharge passa e and a by pass leading from the cyhnder etween the valve and piston and connectine` with the discharo'e passage.

9. The combination with a c and an IOC ' said VXtensible standard therefor, ofa hydraulic lifting and lowering mechanism 'embodying a cylinder, a piston movable therein, operating' upon the chair, a fluid discharge passage from the cylinder, a valve having a passage eonneoti fr theI cylinder Withthe discharge passage W lich is of gradually decreasing area and means for operating said valve relatively yto the movement of the piston. u l0. The combination with the chair and an extensible standard therefor, of a hydraulic raising'and lowering mechanism embodying a cylinder', a piston movable therein and operating upon the chair, a Huid discharge dpassage from the cylinder, a valve carrie by and movable relatively to the piston coperating with and closing said passage and having an escape passage through it the area of escape passage being controlled by the relative movements of the valve and iston.

11. The combination with the chair, and

an extensible standard therefor, of a hydrauhe raising and lowering mechanism embodying acylmder having a valve seat there-- n 1n at its discharge end, a piston operating in the cylinder, the valve at the end of the iston eoperating With the seat, and provi ed With the hollow stem having an aperture therein.

l2. The combination with a chair and an extensible standard therefor, of a hydraulic elevating and lowerin mechanism for the chair embodying a cy 'nder having a valve seat at its end, the iston operating in the cylinder, the Inovablje valve on the iston adapted to coperate with the seat in t 1e cylinder and provided with the tubular perforated stem.

. FRANK RITTER. Vitnesses:

G. WILLARD R101-1, MAUDE A. BENTLEY; 

